JP4196889B2 - Image display device and portable terminal device - Google Patents

Description

  The present invention relates to an image display device capable of displaying images toward a plurality of viewpoints, and a portable terminal device on which the image display device is mounted.

  Conventionally, an image display device capable of displaying different images at a plurality of viewpoints has been studied. As an example, there is a stereoscopic image display device on the premise that a parallax image is displayed as a multi-viewpoint image. In 280 BC, Greek mathematician Euclid considers that "stereoscopicity is the sense that the left and right eyes simultaneously see different images viewed from different directions of the same object" (for example, Non-patent document 1). That is, a stereoscopic image display device can be realized by presenting images with parallax to the left and right eyes, respectively.

  In order to specifically realize this function, many stereoscopic image display methods have been studied so far, and these methods can be roughly divided into a method using glasses and a method using no glasses. Among these, there are anaglyph methods that use the difference in color and polarized glasses methods that use polarized light, etc., but these methods cannot essentially avoid the annoyance of wearing glasses. Therefore, in recent years, a spectacleless method that does not use spectacles has been actively studied. The glassesless method includes a parallax barrier method and a lenticular lens method.

  First, the parallax barrier method will be described. The parallax barrier method is a stereoscopic image display method conceived by Berthier in 1896 and verified by Ives in 1903. FIG. 12 is an optical model diagram showing a stereoscopic image display method using a parallax barrier method. As shown in FIG. 12, the parallax barrier 105 is a barrier (light-shielding plate) in which a large number of thin vertical stripe-shaped openings, that is, slits 105a are formed. A display panel 106 is disposed in the vicinity of one surface of the parallax barrier 105. In the display panel 106, the right-eye sub-pixel 123 and the left-eye sub-pixel 124 are arranged in a direction orthogonal to the longitudinal direction of the slit 105a. A light source 108 is disposed in the vicinity of the other surface of the parallax barrier 105, that is, on the opposite side of the display panel 106.

  A part of the light emitted from the light source 108 is blocked by the parallax barrier 105. On the other hand, the light that has passed through the slit 105 a without being blocked by the parallax barrier 105 passes through the right-eye sub-pixel 123 and becomes a light beam 181, or passes through the left-eye sub-pixel 124 and becomes a light beam 182. At this time, the position of the observer who can recognize the stereoscopic image is determined by the positional relationship between the parallax barrier 105 and the pixels. That is, the right eye 141 of the observer 104 is in the pass band of all the light beams 181 corresponding to the plurality of right eye sub-pixels 123, and the left eye 142 of the observer is in the pass band of all the light beams 182. It is necessary to be. This is a case where the midpoint 143 between the right eye 141 and the left eye 142 of the observer is located within the rectangular three-dimensional visible region 107 shown in FIG.

  Of the line segments extending in the arrangement direction of the right-eye subpixel 123 and the left-eye subpixel 124 in the stereoscopic viewable area 107, the line segment passing through the diagonal intersection 107a in the stereoscopic viewable area 107 is the longest line segment. For this reason, when the middle point 143 is located at the intersection 107a, the tolerance when the position of the observer is shifted in the left-right direction is maximized, and thus the observation position is most preferable. Therefore, in this stereoscopic image display method, the distance between the intersection 107a and the display panel 102 is set as the optimum observation distance OD, and it is recommended to the observer to observe at this distance. A virtual plane in which the distance from the display panel 102 in the stereoscopic visible range 107 is the optimum observation distance OD is referred to as an optimum observation surface 107b. As a result, light from the right eye sub-pixel 123 and the left eye sub-pixel 124 reaches the observer's right eye 141 and left eye 142, respectively. For this reason, the observer can recognize the image displayed on the display panel 102 as a stereoscopic image.

  The above-mentioned parallax barrier method has a problem that it is unsightly and has low visibility because the parallax barrier is initially arranged between the pixel and the eye. However, with the recent realization of liquid crystal display devices, it has become possible to dispose the parallax barrier 105 on the back side of the display panel 102 as shown in FIG. 12, and the problem of visibility has been improved. For this reason, parallax barrier type stereoscopic image display devices are currently under active investigation, and stereoscopic image display devices to which the parallax barrier method is applied have actually been commercialized (see Non-Patent Document 2).

  For example, Table 1 of Non-Patent Document 2 introduces a mobile phone equipped with a 3D-compatible liquid crystal panel. The liquid crystal display panel constituting the stereoscopic image display apparatus in this cellular phone has a diagonal size of 2.2 inches and has a display dot number of 176 horizontal dots × 220 vertical dots. Then, a liquid crystal panel for a switch for turning on / off the effect of the parallax barrier is provided, and the display can be switched between the stereoscopic display and the planar display.

  Next, the lenticular lens method will be described. The lenticular lens system was invented around 1910 by Ives et al., For example, as described in Non-Patent Document 1 described above. FIG. 13 is a perspective view showing a lenticular lens, and FIG. 14 is an optical model diagram showing a stereoscopic display method by a lenticular lens method. As shown in FIG. 13, one surface of the lenticular lens 121 is a flat surface, and the other surface has a semi-cylindrical convex portion (cylindrical lens 122) extending in one direction, and the longitudinal directions thereof are parallel to each other. A plurality are formed so as to be.

  As shown in FIG. 14, in the lenticular lens type stereoscopic image display device, a lenticular lens 121, a display panel 106, and a light source 108 are arranged in this order from the observer side, and on the focal plane of the lenticular lens 121. The pixel of the display panel 106 is located. In the display panel 106, pixels 123 that display an image for the right eye 141 and pixels 124 that display an image for the left eye 142 are alternately arranged. At this time, a group of pixels 123 and 124 adjacent to each other corresponds to each cylindrical lens (convex portion) 122 of the lenticular lens 121. Thereby, the light emitted from the light source 108 and transmitted through each pixel is distributed in the direction toward the left and right eyes by the cylindrical lens 122 of the lenticular lens 121, so that the left and right eyes can recognize different images. A viewer can recognize a stereoscopic image. In this way, the method of causing the observer to recognize a stereoscopic image by displaying the left-eye image and the right-eye image for each eye is called a two-viewpoint method because it forms two viewpoints.

  Next, the size of each part of a stereoscopic image display device including a normal lenticular lens and a display panel will be described in detail. FIG. 15 is an optical model diagram of a binocular stereoscopic image display device using a normal lenticular lens system, and FIG. 16 is an optical model diagram showing a stereoscopic visible range of the binocular stereoscopic image display device. As shown in FIG. 15, the distance between the vertex of the lenticular lens 121 and the pixel of the display panel 106 is H, the refractive index of the lenticular lens 121 is n, the focal length is f, and the lens element array period, that is, Let the lens pitch be L. In the display pixel of the display panel 106, one left-eye sub-pixel 124 and one right-eye sub-pixel 123 are arranged in a set. Let P be the pitch of this pixel. Therefore, the array pitch of the display pixels each consisting of one left-eye sub-pixel 124 and right-eye sub-pixel 123 is 2P. One cylindrical lens 122 is arranged corresponding to each of the two display pixels of the left-eye sub-pixel 124 and the right-eye sub-pixel 123.

The distance between the lenticular lens 121 and the observer is the optimum observation distance OD. The enlarged projection width of the pixel at this distance OD, that is, the left-eye sub-pixel on the virtual plane separated from the lens by the distance OD and parallel to the lens. The width of the projection image of the pixel 124 and the right-eye sub-pixel 123 is e. Furthermore, from the center of the cylindrical lens 122 located in the center of the lenticular lens 121, the distance to the center of the cylindrical lens 122 located at the end of the lenticular lens 121 in the horizontal direction 112 and W _L, located in the center of the display panel 102 and the center of the display pixels comprising a left-eye sub-pixel 124 and a right-eye sub-pixel 123, the distance between the center of the display pixels located at the edge of the display panel 102 in the lens array direction 112 and W _P. Furthermore, the incident angle and the outgoing angle of light in the cylindrical lens 122 located at the center of the lenticular lens 121 are α and β, respectively, and the incident angle of the light in the cylindrical lens 122 located at the end of the lenticular lens 121 in the lens arrangement direction 112. And γ and δ are the exit angles. Furthermore, the distance W the difference between _L and the distance W _P is C, the distance W number of pixels contained in the area of _P is referred to as the 2m.

  Since the arrangement pitch L of the cylindrical lenses 122 and the arrangement pitch P of the pixels are related to each other, the other is determined according to one, but usually the lenticular lens is often designed according to the display panel. Therefore, the pixel arrangement pitch P is treated as a constant. The refractive index n is determined by selecting the material of the lenticular lens 121. On the other hand, the observation distance OD between the lens and the observer, and the pixel enlargement projection width e at the observation distance OD are set to desired values. These values are used to determine the distance H and lens pitch L between the vertex of the lens and the pixel. From Snell's law and geometrical relationships, the following formulas 1 to 6 are established.

  Also, the following formulas 7 to 9 are established.

  From the above formulas 1 to 3, the following formulas 10 to 12 are established, respectively.

  Further, from the above formulas 6 and 9, the following formula 13 is established.

Furthermore, from the above formulas 7 and 8, the following formula 14 is established.

  Furthermore, the following formula 15 is established from the above formula 5.

  As described above, normally, in order to make the distance H between the apex of the lenticular lens and the pixel equal to the focal length f of the lenticular lens, the following formula 16 is established, and if the curvature radius of the lens is r, the curvature is The radius r is obtained by the following formula 17.

  As shown in FIG. 16, an area where light from all right-eye subpixels 123 reaches is a right-eye area 171, and an area where light from all left-eye subpixels 124 reaches is a left-eye area 172. To do. The observer can recognize a stereoscopic image by positioning the right eye 141 in the right eye region 171 and the left eye 142 in the left eye region 172. However, since the observer's binocular interval is constant, the right eye 141 and the left eye 142 cannot be placed at arbitrary positions in the right eye region 171 and the left eye region 172, respectively, and the binocular interval is maintained at a constant value. It is limited to the area that can. That is, stereoscopic vision is possible only when the midpoint of the right eye 141 and the left eye 142 is located in the stereoscopic visibility range 107. At the position where the distance from the display panel 106 is the optimal observation distance OD, the length along the horizontal direction 112 in the stereoscopic view area 107 is the longest, and thus the tolerance when the position of the observer is shifted in the horizontal direction 112. Is the maximum. For this reason, the position where the distance from the display panel 106 is the optimum observation distance OD is the most ideal observation position.

  Whereas the parallax barrier method described above is a method of “hiding” unnecessary light by a barrier, the lenticular lens method is a method of changing the light traveling direction, and in principle the brightness of the display screen by providing a lenticular lens. There is no drop in height. For this reason, application to portable devices and the like where high luminance display and low power consumption performance are particularly important is considered promising.

  An example of developing a stereoscopic image display device using a lenticular lens method is described in Non-Patent Document 2 described above. The liquid crystal display panel constituting the stereoscopic image display device of this stereoscopic image display device has a diagonal size of 7 inches and a display dot number of 800 dots wide × 480 dots wide. The stereoscopic display and the flat display can be switched by changing the distance between the lenticular lens and the liquid crystal display panel by 0.6 mm.

  As another example of an image display device that can display different images at a plurality of viewpoints, a multi-image simultaneous display display is disclosed (see Patent Document 1). The display described in Patent Document 1 uses the image distribution function of the lenticular lens to simultaneously display different planar images for each observation direction under the same conditions, and is different from different directions for a plurality of different observers. A planar image can be observed simultaneously on one display. FIG. 17 is a perspective view showing the multi-image simultaneous display. As shown in FIG. 17, in this multiple image simultaneous display display, a lenticular lens 121 and a display panel 106 are arranged in this order from the viewer 104 side. In the display panel 106, first viewpoint pixels 125 that display images for the first viewpoint and second viewpoint pixels 126 that display images for the second viewpoint are alternately arranged. At this time, a group of pixels 125 and pixels 126 adjacent to each other corresponds to each cylindrical lens (convex portion) 122 of the lenticular lens 121. Thereby, since the light of each pixel is distributed in a different direction by the cylindrical lens 122 of the lenticular lens 121, it becomes possible to recognize different images at different positions. By using this multi-image simultaneous display display, it is possible to reduce the installation space, the electricity bill, and the like as compared with the case where a display for the number of persons is prepared.

  On the other hand, liquid crystal display devices have advantages such as low power consumption, and are particularly frequently used in small and medium-sized applications such as portable terminals. Since the liquid crystal display panel constituting the liquid crystal display device is a non-self-luminous type that performs display by modulating external light, some external light source is necessary. In a transmissive liquid crystal display device that is most widely used at present, the liquid crystal display panel is a transmissive liquid crystal display, and an illuminating unit called a backlight unit is installed on the back side of the liquid crystal display panel as viewed from the observer (non-display). (See Patent Document 3). FIG. 1 of Non-Patent Document 3 describes the structure of a backlight unit for a liquid crystal panel. In general, a backlight unit includes a light guide plate that propagates light from a light source, a light source called an edge light (side light) disposed on a side surface of the light guide plate, and an optical sheet disposed on an observer side of the light guide plate. It is composed of And the light emitted from the edge light is partly emitted toward the viewer while propagating through the light guide plate. After the optical characteristics such as light uniformity and angle distribution are shaped by the optical sheet, the light is transmitted. Passes through the LCD panel and enters the viewer. FIG. 18 is an optical model diagram of a conventional stereoscopic image display apparatus using a lenticular lens. As described in Non-Patent Document 3, as the optical sheet of the backlight unit, a prism sheet and a lens sheet made up of a large number of prisms or lenses are frequently used. As shown in FIG. Convex portions based on the prism or lens structure exist on the surfaces of the prism sheet and the lens sheet.

JP-A-6-332354 (FIG. 9) Chihiro Masuda, “3D Display”, Sangyo Tosho Co., Ltd., p. 1 Nikkei Electronics, January 6, 2003, no. 838, p. 26-27 Akira Tanaka, “Latest trend of LCD backlight”, Monthly Display, June 1997, p75

  However, the conventional techniques described above have the following problems. In portable terminal devices, thinning is important from the viewpoint of improving portability, and thinning is also desired for image display devices mounted on portable terminal devices. Therefore, the present inventors have reduced the distance between the pixels constituting the image display device and the backlight unit in order to reduce the thickness of the image display device. As a result, stripes appear in the display image, and the display quality is significantly reduced. The problem of doing was clarified.

  The present invention has been made in view of such problems, and an object of the present invention is to provide an image display device that is thin and excellent in display quality and a portable terminal device that includes the image display device.

In the image display device according to the first aspect of the present invention, at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are juxtaposed in a first direction, respectively, a display panel a second viewpoint pixel including table示単position are arranged in a plurality matrix, wherein the pixels for the first viewpoint light and the second viewpoint emitted from pixels for in each display unit A lens for distributing the emitted light in different directions inclined in the first direction within a plane perpendicular to the display panel, and a plurality of lenses arranged near the back surface of the display panel and disposed on the display panel side surface An illumination member formed with a convex portion, and when the distance between the pixel and the convex portion is S, the focal length of the lens is f, and the arrangement pitch of the lenses is L, the illumination wherein between the convex portions adjacent in the member first The distance in the direction of V is characterized by satisfying the following equation 18.

  In the present invention, since it is possible to reduce the influence of the directivity distribution of the emitted light caused by the projections of the illumination member, it is possible to reduce the thickness of the image display device without degrading the display quality.

  The focal length f may be shorter than the distance between the lens and the pixel. Thereby, since the focal position of a lens can be set to the lens side rather than a pixel, the light beam of a wider area | region on an illumination member can be used. As a result, since the distance between the adjacent convex portions can be increased, the influence of the directivity distribution of the emitted light caused by the convex portions can be reduced, and the image display device can be reduced without degrading the display quality. Thinning can be achieved. Further, since the focal position of the lens is deviated from the pixel surface, the influence of the non-display area between the pixels is alleviated and display quality deterioration due to the non-display area can be prevented.

  Moreover, when the distance V between the adjacent convex parts in an illumination member has in-plane distribution, it is preferable that this distance V is the minimum value among the distances between adjacent convex parts. Thereby, even if the distance V has an in-plane distribution, the image display device can be thinned without deteriorating the display quality.

In the image display device according to the second aspect of the present invention, at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are juxtaposed in a first direction, respectively. a display panel a second viewpoint pixel including table示単position are arranged in a plurality matrix, wherein the pixels for the first viewpoint light and the second viewpoint emitted from pixels for in each display unit A lens for distributing the emitted light in different directions inclined in the first direction within a plane perpendicular to the display panel, and a plurality of lenses arranged near the back surface of the display panel and disposed on the display panel side surface A projection member regularly formed, and a distance in the first direction between adjacent projections in the illumination member is 0.6 mm or less.

  In the present invention, in a two-viewpoint image display device in which a transmissive liquid crystal panel having a pixel pitch of 0.15 mm, which is currently most utilized as a display panel for a portable terminal, is used, and the display pixel is composed of two sub-pixels, The image display device can be reduced in thickness without degrading display quality.

The lens is, for example, a lenticular lens in which a plurality of cylindrical lenses are arranged so that their longitudinal directions are parallel to each other. And when the said convex part is extended in one direction, you may make the direction where the said convex part extends, and the longitudinal direction of the said cylindrical lens mutually parallel. The convex portions may be formed in a matrix. Thereby, for example, in the case of an illuminating member in which an optical sheet in which convex portions are formed on a backlight is disposed, the convex portions are formed by using the optical sheet in which the convex portions are formed in a matrix. the same effect as when used by laminating two sheets of optical sheets extending in one direction Ru are obtained, et al. As a result, the number of constituent members can be reduced and the cost can be reduced.

  Alternatively, the lens is, for example, a fly-eye lens in which a plurality of convex lenses are arranged in a matrix. Thereby, since the light radiate | emitted through a lens can be distributed to 4 directions, a different image can be distributed and displayed in two dimensions.

In the image display device according to the third aspect of the present invention, at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are juxtaposed in a first direction. a display panel a second viewpoint pixel including table示単position are arranged in a plurality matrix, wherein the pixels for the first viewpoint light and the second viewpoint emitted from pixels for in each display unit A lenticular lens having a cylindrical lens that distributes the emitted light in different directions inclined in the first direction within a plane perpendicular to the display panel, and the display panel disposed in the vicinity of the back surface of the display panel A plurality of convex portions extending in a direction inclined by an angle θ with respect to the longitudinal direction of the cylindrical lens on the side surface, and the distance between the pixel and the convex portion is S, Said The focal length of the lens f, when the arrangement pitch of the lens L, and the pixel pitch in the longitudinal direction of the cylindrical lens and P _V, the distance V between the convex portions adjacent in the illumination member satisfies the following formula 19 It is characterized by.

  In the present invention, it is possible to prevent the display quality from being deteriorated due to the convex portion of the illumination member by utilizing the one-dimensional lens action of the cylindrical lens. As a result, a thin image display device with excellent display quality can be obtained.

In the image display device according to the fourth invention of the present application, at least a pixel for displaying an image for a first viewpoint and a pixel for displaying an image for a second viewpoint are juxtaposed in a first direction. a display panel a second viewpoint pixel including table示単position are arranged in a plurality matrix, wherein the pixels for the first viewpoint light and the second viewpoint emitted from pixels for in each display unit A lenticular lens having a cylindrical lens that distributes the emitted light in different directions inclined in the first direction within a plane perpendicular to the display panel, and the display panel disposed in the vicinity of the back surface of the display panel A lighting member having a plurality of convex portions formed in a matrix on the side surface, wherein the distance between the pixel and the convex portion is S, the focal length of the lens is f, and the arrangement pitch of the lenses is L, the above When the pixel pitch in the longitudinal direction of the command helical lens and P _V, a distance V _V between adjacent protrusions of the lighting member in the direction inclined by an angle θ to the longitudinal direction of the cylindrical _lens, and said cylindrical lens A distance V between adjacent convex portions of the illumination member in a direction orthogonal to a direction inclined by an angle θ with respect to the longitudinal direction of the lens satisfies the following Expression 21.

  For example, the lenticular lens is arranged so that one side of the display panel and the longitudinal direction of the cylindrical lens are parallel to each other. Thereby, it is possible to display an image without giving the user a sense of incongruity.

  The focal length f may be shorter than the distance between the lenticular lens and the pixel. Thereby, since the focal position of a lens can be set to the lens side rather than a pixel, the light beam of a wider area | region on an illumination member can be used. As a result, the distance between the adjacent convex portions can be increased, and the influence of the directivity distribution of the emitted light caused by the convex portions can be mitigated. Thinning can be achieved. Further, since the focal position of the lens is deviated from the pixel surface, the influence of the non-display area between the pixels is reduced, and display quality deterioration due to the non-display area can be prevented.

  Furthermore, a light diffusion member may be provided between the display panel and the illumination member. Thereby, the influence on the display image of the directivity distribution of the emitted light resulting from the convex part of an illuminating member can be relieved. As a result, a thin image display device with excellent display quality can be obtained.

  Furthermore, the image display device may be a stereoscopic image display device. Thereby, a some parallax image can be displayed and a favorable stereo image can be displayed.

  Alternatively, the image display device may be a flat image display device. Thereby, for example, when this image display device is mounted on a mobile terminal device, an image for a plurality of viewpoints can be observed only by changing the angle of the mobile terminal device. In particular, when images for a plurality of viewpoints are related, each image can be referred to by a simple method of changing the observation angle, which greatly improves convenience. In addition, when images for a plurality of viewpoints are arranged in the vertical direction, the observer can always observe the images for each viewpoint with both eyes, so that the visibility of the images for each viewpoint can be improved. Furthermore, a liquid crystal display panel may be used as the display panel.

  A mobile terminal device according to a fifth invention of the present application includes the above-described image display device. Examples of the portable terminal device include a mobile phone, a personal information terminal, a game machine, a digital camera, and a digital video.

  According to the present invention, since it is possible to reduce the influence of the directivity distribution of the emitted light caused by the convex portions formed on the illumination member, it is possible to reduce the thickness of the image display device without reducing the display quality. it can.

  The inventors of the present invention have made extensive studies in order to solve the above-described problems, to thin the image display device such as the above-described stereoscopic image display device and the multiple image simultaneous display display, and to mount them on a mobile terminal device. . As a result, the following knowledge about the phenomenon in which a striped pattern appears in the display image was obtained. In the stereoscopic image display device, if the purpose is simply to display a stereoscopic image, as shown in FIG. 16, it is sufficient to consider only the optical model from the pixel to the viewer side. 18, the distance from the display pixel (the right-eye sub-pixel 123 and the left-eye sub-pixel 124) to the optical sheet 151 provided in the backlight unit 150 and the optical sheet 151 as illustrated in FIG. It is necessary to examine the shape of the protrusions formed on the surface of the film.

  As shown in FIG. 18, generally, a stereoscopic image display device is provided with a lenticular lens 121, a display panel 106, and a backlight unit 150 in order from the observer side. The display panel 106 is, for example, a transmissive liquid crystal panel. On the surface of the backlight unit 150 on the display panel side, an optical sheet 151 having a convex portion extending in one direction is disposed. The shape of the convex portions formed on the surface of the optical sheet 151 is, for example, a prism shape, and the repetition pitch of the concave portions is V. The focal length of the cylindrical lens 122 constituting the lenticular lens 121 is f. Since the focal point in this stereoscopic image display device is set to the display pixel (the left-eye sub-pixel 124 and the right-eye sub-pixel 123), the focal length f is the apex of the cylindrical lens 122 shown in FIG. Is equal to the distance H. Further, the convex portions on the surface of the optical sheet 151 are arranged in one direction, and the longitudinal direction thereof coincides with the longitudinal direction of the cylindrical lens 122. That is, the arrangement direction of the convex portions on the surface of the optical sheet 151 coincides with the arrangement direction of the cylindrical lenses 122.

  Here, the arrangement pitch of the cylindrical lenses 122 is L, and the distance from the display pixel to the optical sheet 151 is S. Light that has passed through a certain point of the display pixel travels toward the lenticular lens while spreading, but a light beam incident on one cylindrical lens 122 constituting the lenticular lens 121 has a lens pitch L as a base and a focal length f as a height. Form a triangle. On the other hand, the light ray group 1 emitted from the backlight unit 150 and directed to a certain point of the display pixel also forms a triangle. The height of this triangle is the distance S from the display pixel to the optical sheet 151, and the length of the base is defined as X. Since these two triangles have a similar relationship, the relationship of the following formula 22 is established.

  Light that has passed through a certain point of the display pixel and passed through the cylindrical lens 122 is projected onto the observation surface, and has a one-to-one correspondence with the point of the pixel. Therefore, the finite range X on the optical sheet 151 corresponds to a certain point on the observation surface, and the finite range X on the optical sheet 151 changes depending on the position of the point on the observation surface. Here, attention is focused on the luminance distribution of the optical sheet 151 in the finite range X. If the luminance distribution varies depending on the position of the finite range X, the brightness on the observation surface varies. Since this fluctuation is observed while being superimposed on the image to be displayed, the image quality is significantly lowered.

  As a factor in which the luminance distribution varies depending on the position of the finite range X, there is a luminance distribution caused by a convex portion on the surface of the optical sheet 151. The inclination angle of the convex portion on the surface of the optical sheet 151 varies depending on the position. For this reason, the luminance distribution of the emitted light varies depending on the position in the convex portion, that is, the position on the optical sheet 151. As a result, the finite range X on the optical sheet 151 becomes smaller than the repetition pitch V of the convex portion, that is, the following Expression 23 is established, and the influence of the luminance distribution of the emitted light caused by the convex portion on the surface of the optical sheet 151 is affected. It will be received greatly.

  In order to examine this problem in detail, a transmissive liquid crystal display panel with a pixel pitch P of 0.15 mm, which is currently widely used for cellular phones, is used, and two viewpoints having a front pixel composed of two sub-pixels. Consider a stereoscopic image display apparatus. The thickness of the thin glass substrate in this transmissive liquid crystal display panel is the most general-purpose 0.7 mm. For this reason, the distance between the lens and the pixel and the focal length are both set to 0.7 mm. Further, in the space from the display pixel to the optical sheet, in addition to the above-mentioned glass substrate having a thickness of 0.7 mm, a polarizing plate (thickness: 0.3 mm), which is essential for the transmission type liquid crystal display panel, has a luminance. A multilayer optical film (thickness 0.2 mm) for improving, and a light-transmitting adhesive film (thickness 0.2 mm) for fixing the backlight unit and the liquid crystal display panel to each other are provided in this order. Here, when using an optical sheet on which convex portions having a pitch V larger than 0.6 mm are used, the distance from the display pixel to the optical sheet must be increased in order to prevent the quality of the display image from deteriorating. I must. For example, when using an optical sheet having a convex portion pitch V of 1 mm, the distance from the display pixel to the optical sheet needs to be 2 mm. For this reason, useless gaps are generated in the space from the display pixels to the optical sheet, and the thickness of the stereoscopic image display device increases. On the other hand, if the useless space from the display pixels to the optical sheet is eliminated in order to reduce the thickness of the image display device, the influence of the luminance distribution due to the convex portion on the surface of the optical sheet is increased, and the display image quality is significantly reduced. To do.

  Hereinafter, an image display device according to an embodiment of the present invention will be specifically described with reference to the accompanying drawings. First, the stereoscopic image display apparatus according to the first embodiment of the present invention will be described. FIG. 1 is an optical model diagram showing the stereoscopic image display apparatus of this embodiment. In FIG. 1, components other than the pixels in the display panel are omitted for easy viewing of the drawing. As shown in FIG. 1, in the stereoscopic image display apparatus 10 of this embodiment, the lenticular lens 3, the display panel 2, and the backlight unit 5 are provided in order from the observer side. The display panel 2 in the image display device 1 is, for example, a transmissive liquid crystal panel, and the display pixels of the display panel are composed of adjacent right-eye sub-pixels 42 and left-eye sub-pixels 41. Each display pixel is arranged along the longitudinal direction of the cylindrical lens 3a, and the lenticular lens 3 is arranged so that one cylindrical lens 3a corresponds to this array of display pixels.

  Further, on the surface of the backlight unit 5 on the display panel 2 side, an optical sheet 51 in which a convex portion extending in one direction is formed on one surface, and the surface on which the convex portion is formed is on the display panel 2 side. Are arranged as follows. The shape of the convex portions formed on the optical sheet 51 is, for example, a prism shape, and the distance between adjacent convex portions, that is, the repetition pitch of the convex portions is V. Furthermore, in the image display device 10 of the embodiment, the focal point is set to the display pixel, and the focal length f of the cylindrical lens 3a constituting the lenticular lens 3 is equal to the distance between the apex of the lens and the display pixel. Yes. Furthermore, the convex portions of the optical sheet 51 are arranged in one direction, and the longitudinal direction thereof coincides with the longitudinal direction of the cylindrical lens 3a. That is, the arrangement direction of the convex portions of the optical sheet 51 and the arrangement direction of the cylindrical lenses 3a coincide. When the arrangement pitch of the cylindrical lenses 3a is L and the distance between the display pixel and the optical sheet 51 is S, the pitch V of the convex portions in the optical sheet 51 satisfies the following Expression 24.

  Next, the operation of the stereoscopic image display apparatus 10 according to the present embodiment will be described by paying attention to a certain point of display pixels on the display panel 2. The light emitted from the backlight unit 5 travels at various angles. Accordingly, the light beam that has passed through a certain point of the display pixel diffuses and travels toward the lenticular lens 3. Therefore, when attention is paid to one cylindrical lens 3a constituting the lenticular lens 3, a light beam incident on the cylindrical lens 3a forms a triangle having a lens pitch L as a base and a focal length f as a height. On the other hand, a light ray group emitted from the backlight unit 5 and directed to a certain point of the display pixel also forms a triangle. The height of this triangle is the distance S from the display pixel to the optical sheet 51. Since these two triangles have a similar relationship, if the length of the base of this triangle is defined as X, the relationship of the following formula 25 is established.

  The length X of the base of the triangle shown in Equation 25 is nothing but the right side in Equation 24 described above. That is, when focusing on a certain point of the display pixel in the display panel 2, the stereoscopic image device 10 of the present embodiment is arranged at the bottom of the triangle formed by the light ray group emitted from the backlight unit 5 and incident on the certain point of the display pixel. The length X is equal to or greater than the pitch V of the prismatic convex portions in the optical sheet 51 of the backlight unit 5. The prism-like convex portions on the surface of the optical sheet 51 have different surface inclination angles depending on their positions, so that the directivity distribution of the light emitted from the backlight unit 5 also differs depending on the emission position. For example, when the length X of the base of the triangle is smaller than the pitch V of the convex portions, the influence of the directivity distribution of the emitted light depending on the position of the convex portions becomes large. However, in the stereoscopic image display device 10 of the present embodiment, the length X of the base of the triangle is equal to or greater than the pitch V of the convex portions, so that the influence of the directivity distribution can be reduced.

  In addition, light that passes through a certain point of the display pixel and passes through the cylindrical lens 3a is projected onto the observation surface, and has a one-to-one correspondence with the point of the display pixel. Therefore, the finite range X on the optical sheet 51 corresponds to a certain point on the observation surface, and the finite range X on the optical sheet 51 changes corresponding to the position of the point on the observation surface. Here, attention is focused on the luminance distribution of the optical sheet 51 in a certain finite range X. If the directivity distribution of emitted light, that is, the luminance distribution differs depending on the position on the optical sheet in the finite range X, the brightness on the observation surface varies depending on the position. This variation in brightness is observed superimposed on the image to be displayed, so that the image quality is significantly reduced. In order to solve this problem, it is effective to make the luminance distribution in the finite range X uniform regardless of the position on the optical sheet. As described above, in the stereoscopic image display device 1 of the present embodiment, the above mathematical formula 24 is established, and the finite range X is set to be equal to or higher than the pitch V of the prismatic convex portions in the optical sheet 51. The luminance distribution at X can be made uniform regardless of the position on the optical sheet 51. Thereby, a thin image display device with excellent display quality can be realized.

Next, regarding the effect of the three-dimensional image display device 10 of the present embodiment, as a display panel 2, a transmissive liquid crystal display in which a glass substrate (not shown) has a thickness of 0.7 mm and a pixel pitch is 0.15 mm. A two-viewpoint stereoscopic image display device using a panel will be described in detail as an example. The distance between the apex of the lenticular lens 3 and the display pixel and the focal length f in this stereoscopic image display device are both the thickness of a glass substrate (not shown), that is, 0.7 mm. Further, between the display pixel and the optical sheet 51, in addition to the above-described glass substrate (not shown), a polarizing plate (not shown) essential for a transmissive liquid crystal display panel, for improving luminance. A multilayer optical film (not shown), a light transmissive adhesive film (not shown) for fixing the backlight unit 5 and the liquid crystal display panel to each other are provided in this order. These thickness polarizer 0.3 mm, the optical fill beam is 0.2 mm, the adhesive film is 0.2 mm. In the stereoscopic image display device having such a configuration, by setting the pitch V of the convex portions of the optical sheet 51 to 0.6 mm or less, the distance S from the display pixel to the optical sheet 51 is the minimum for providing each member. The value can be set to 1.4 mm or less.

  On the other hand, if the pitch V of the convex portions of the optical sheet 51 is larger than 0.6 mm, the distance from the display pixels to the optical sheet 51 must be increased in order to prevent display quality deterioration. Specifically, when the pitch V of the convex portions of the optical sheet 51 is 1 mm, the distance S from the display pixel to the optical sheet 51 must be 2 mm, which is useless between the display pixel and the optical sheet 51. A gap is generated, resulting in an increase in the thickness of the image display device. In this way, by setting the pitch of the convex portions of the optical sheet 51 provided in the backlight unit 5 to 0.6 mm or less, a thin stereoscopic image display device excellent in display quality can be realized.

  FIG. 2 is a perspective view showing a portable terminal device on which the stereoscopic image display device shown in FIG. 1 is mounted. As shown in FIG. 2, the stereoscopic image display device 10 is mounted on a mobile terminal device 9 such as a mobile phone, for example.

  In the stereoscopic image display device 10 according to the present embodiment, an optical sheet having prism-shaped convex portions extending in one direction on the surface is used. However, the present invention is not limited to this, and the prism-shaped projection is used. An optical sheet having convex portions arranged in a matrix can also be used. In addition, for example, two optical sheets on which prism-shaped convex portions extending in one direction are arranged so that the directions in which the convex portions extend are orthogonal to each other in a plan view. An optical sheet can also be provided. In that case, it is preferable that the pitch V of the optical sheet in which the direction in which the convex portion extends is the same as the arrangement direction of the cylindrical lenses 3 a be in the range defined by the above formula 24.

  Further, in the stereoscopic image display device 10 of the present embodiment, the convex portion is formed on the optical sheet 51, but the present invention is not limited to this, and for example, a light guide plate provided in the backlight unit 5 Even if a convex portion is formed on the surface of the surface, the same effect can be obtained by setting the pitch of the convex portion within the range of the above-described Expression 23. When the convex portion has an in-plane distribution, it is desirable that the minimum value of the pitch V satisfies the above formula 24. Further, the shape of the convex portion is not limited to the prism shape, and the present invention has a convex portion on the surface of the backlight unit 5, and the convex portion is present. It can be applied when the distribution is different. Note that a light diffusing member, specifically an optical film having a light scattering effect, or the like may be provided on the convex portion formed in the backlight unit 5. Thereby, the influence of a convex part can be reduced.

  Furthermore, in the stereoscopic image display device 10 of the present embodiment, a transmissive liquid crystal panel is used as the display panel 2, but the present invention is not limited to this, and any display panel using the backlight unit 5 can be applied. Is possible. The driving method of the liquid crystal panel may be an active matrix method such as a TFT (Thin Film Transistor) method and a TFD (Thin Film Diode) method, or a passive matrix such as an STN (Super Twisted Nematic Liquid Crystal) method. The method may be used. Furthermore, the image display device 1 of the present embodiment can be applied not only to mobile phones but also to various mobile terminal devices such as PDAs (Personal Digital Assistants), game machines, digital cameras, and digital video cameras. it can.

  Next, a stereoscopic image display apparatus according to the second embodiment of the present invention will be described. FIG. 3 is an optical model diagram of the stereoscopic image display apparatus of the present embodiment, and FIG. 4 is a perspective view showing a fly-eye lens. As shown in FIG. 3, the stereoscopic image display device 21 of the present embodiment uses the first embodiment described above except that a fly-eye lens 8 in which lenses are arranged in a matrix is used instead of a lenticular lens. It is the same as that of the three-dimensional image display apparatus 10 of a form. In the stereoscopic image display device 20 of the present embodiment, since the fly-eye lens 8 is used, the pixel light emitted through the lens can be distributed in four directions, up, down, left, and right. As a result, a stereoscopic image can be displayed even when the arrangement direction of the stereoscopic image display device 20 is rotated.

  When the lens pitch of the fly-eye lens 8 varies depending on the arrangement direction, it is desirable that the convex pitch P in the optical sheet 51 be in the range of the above formula 24 with respect to the small pitch direction. Note that, in the stereoscopic image display device 20 of the present embodiment, as in the stereoscopic image display device 10 of the first embodiment described above, the arrangement of the convex portions formed on the surface of the optical sheet 51 is unidirectional and matrix. Either shape can be used.

  Further, for example, when two optical sheets 51 having prism-shaped convex portions formed in one direction are arranged so that the longitudinal directions of the convex portions are orthogonal to each other in plan view, they are arranged on the display panel 2 side. It is preferable that the pitch V of the optical sheet is in the range defined by the above formula 24. This is because the optical sheet on the display panel 2 side has a smaller distance between the display pixels and the optical sheet, and thus the conditions for preventing display quality from degrading are severer. Further, the configuration and effects of the stereoscopic image display device 21 of the present embodiment other than those described above are the same as those of the stereoscopic image display device 1 of the first embodiment described above.

Next, a stereoscopic image display apparatus according to the third embodiment of the present invention will be described. FIG. 5 is a perspective view showing a part of the stereoscopic image display apparatus according to the present embodiment. In FIG. 5, only a part of the lenticular lens, a part of the optical sheet, and one display pixel are shown, and other components are omitted. As shown in FIG. 5, in the stereoscopic image display device 30 of the present embodiment, the longitudinal direction of the cylindrical lens 3 a that constitutes the lenticular lens 3 and the direction in which the prism-shaped convex portion formed on the surface of the optical sheet 51 extends. Does not match. Then, the longitudinal and angle between the direction in which the prismatic protrusion extending cylindrical lens 3a and theta, the pixel pitch in the longitudinal direction of the cylindrical lens 3a is taken as P _V, the repetition pitch of the convex portion of the optical sheet 51 V satisfies the following Expression 26.

6A and 6B are cross-sectional views showing the backlight unit of the stereoscopic image display device of the present embodiment, and FIG. 6A is a cross-sectional view taken along line AA shown in FIG. 6 (b) is a sectional view taken along line BB. In the stereoscopic image display device of the present embodiment, the lenticular lens 3 and the optical sheet 51 are arranged so that the angle formed by the longitudinal direction of the cylindrical lens 3a and the direction in which the convex portion of the optical sheet 51 extends is θ. Therefore, the relative positions of the convex shapes in FIGS. 6A and 6B differ by a value (P _V × tan θ).

  The arrangement direction component of the cylindrical lenses 3a at the pitch V of the convex portions of the optical sheet 51 is a value (V / cos θ).

Since the cylindrical lens 3 does not have a lens effect in the continuous direction, the effect of the optical sheet 51 can be considered as an effect obtained by superimposing the arrangement of the convex portions shown in FIGS. Therefore, the convex portion of the optical sheet 51 is equivalent to the case where the width of the convex portion is increased by a value (P _V × tan θ). Since the arrangement direction component of the cylindrical lenses 3a at the pitch V of the convex portion of the optical sheet 51 is indicated by a value (V / cos θ), in the stereoscopic image display device of the present embodiment, when the following Expression 27 is satisfied. An effect equivalent to that of the stereoscopic image display device 1 of the first embodiment is obtained.

  It is to be noted that the above formula 27 is rearranged to be the above formula 26. According to the three-dimensional image display device 30 of the present embodiment, the optical sheet 51 formed with a convex portion extending in one direction is inclined with respect to the longitudinal direction of the cylindrical lens 3 a constituting the lenticular lens 3, whereby the cylindrical image is displayed. By utilizing the one-dimensional lens action of the lens, it is possible to prevent a reduction in display quality due to the convex portion of the optical sheet 51, and to realize a thin stereoscopic image display device with excellent display quality.

  In the three-dimensional image display device of the present embodiment, the optical sheet 51 is rotated with respect to the longitudinal direction of the cylindrical lens 3a constituting the lenticular lens 3, but the longitudinal direction of the cylindrical lens 3a and the optical direction of the cylindrical lens 3a are optical. For example, the optical sheet 51 is disposed so that the direction in which the convex portion extends is parallel to a certain side of the stereoscopic image display device, and the lenticular lens is not required. 3 may be rotated and arranged. However, when the lenticular lens 3 is disposed at an angle, the user feels uncomfortable. Therefore, the lenticular lens 3 is preferably disposed such that the longitudinal direction of the cylindrical lens 3a is parallel to one side of the display panel. Thereby, a user's discomfort can be removed.

Next, a fourth embodiment of the present invention will be described. FIG. 7 is a perspective view showing a part of the stereoscopic image display apparatus according to the present embodiment. In FIG. 7, only a part of the lenticular lens, a part of the optical sheet, and one display pixel are shown, and other components are omitted. As shown in FIG. 7, the stereoscopic image display device 40 of the present embodiment uses an optical sheet 52 in which convex portions are formed in a matrix instead of the optical sheet 51 in which convex portions extending in one direction are formed. is doing. The remaining configuration of the stereoscopic image display device 40 of the present embodiment is the same as that of the stereoscopic image display device 30 of the third embodiment described above. In the stereoscopic image display device 40 of the present embodiment, the longitudinal direction of the cylindrical lens 3 a constituting the lenticular lens 3 does not coincide with the arrangement direction of the convex portions formed on the surface of the optical sheet 51. The pitch V _V of the convex portions in the direction inclined by the angle θ with respect to the direction in which the cylindrical lens 3a extends satisfies the following Expression 28. Incidentally, P _V in the following equation 28 is the pixel pitch in the longitudinal direction of the cylindrical lens 3a.

  Accordingly, since one or more convex portions can be included in one sub-pixel (the right-eye sub-pixel 42 or the left-eye sub-pixel 41), the convex portion is obtained through the one-dimensional lens action of the cylindrical lens 3a. It is possible to increase the spatial frequency equivalently, and to prevent the display quality from being deteriorated due to the convex portion.

  According to the three-dimensional image display device 40 of the present embodiment, the cylindrical lens 3a is arranged by being inclined with respect to the longitudinal direction of the cylindrical lens 3a constituting the lenticular lens 3 by arranging the optical sheet 52 formed with convex portions in a matrix shape. By using the one-dimensional lens action, it is possible to prevent the display image quality from being deteriorated due to the convex portion, and thus it is possible to realize a thin stereoscopic image display device with excellent display quality.

  Further, when the optical sheet 52 having convex portions formed in a matrix is used, the same effect as when two optical sheets having convex portions extending in one direction are used can be obtained, so the number of constituent members is small. Thus, the manufacturing cost can be reduced.

  Next, a stereoscopic image display device according to a fifth embodiment of the present invention will be described. FIG. 8 is an optical model diagram showing the stereoscopic image display apparatus according to this embodiment. In FIG. 8, components other than the pixels in the display panel 2 are omitted in order to make the drawing easier to see. In the stereoscopic image display device 50 of the present embodiment, the focal point of the cylindrical lens 3a constituting the lenticular lens 3 is set closer to the lenticular lens 3 than the display pixel, and the focal length f is between the apex of the lens and the pixel. It is smaller than the distance H. That is, the following formula 29 is established.

  In the stereoscopic image display device 50 according to the present embodiment, since the focal position of the lens can be set closer to the lenticular lens 3 than the display pixel, a light beam in a wider area on the backlight unit 5 can be used. . As a result, an optical sheet having a wide pitch between the convex portions can be used, so that the influence of the directivity distribution of the emitted light caused by the convex portions can be reduced. Further, since the focal position of the lens is displaced from the pixel surface, the influence of the non-display area between the pixels can be reduced, and the deterioration of the display image due to the non-display area can be reduced. Note that the other configurations and effects of the stereoscopic image display apparatus 50 of the present embodiment are the same as those of the stereoscopic image display apparatus 10 of the first embodiment described above. However, in the stereoscopic image display device 50 of the present embodiment, S is the distance from the lens focal position to the optical sheet 51.

  Next, a stereoscopic image display device according to a sixth embodiment of the present invention will be described. FIG. 9 is an optical model diagram showing the stereoscopic image display apparatus of the present embodiment. In the stereoscopic image display device of the present embodiment, the focal point of the lens constituting the fly-eye lens 8 is set closer to the fly-eye lens 8 than the display pixel. For this reason, the focal length f is smaller than the distance H between the apex of the lens and the pixel, and the following Expression 30 is established. The remaining configuration of the stereoscopic image display device 60 of the present embodiment is the same as that of the stereoscopic image display device 20 of the second embodiment described above.

  In the stereoscopic image display device 60 of the present embodiment, in addition to the effects of the stereoscopic image display device 20 of the second embodiment described above, the focal position of the lens is set closer to the fly-eye lens 8 than the display pixels. Therefore, a wider area of the light beam on the backlight unit 5 can be used. As a result, an optical sheet having a wide pitch between the convex portions can be used, so that the influence of the directivity distribution of the emitted light caused by the convex portions can be reduced. Further, since the focal position of the lens is displaced from the pixel surface, the influence of the non-display area between the pixels can be reduced, and the deterioration of the display image due to the non-display area can be reduced.

  Next, a portable terminal device according to a seventh embodiment of the present invention will be described. FIG. 10 is a perspective view showing the portable terminal device of this embodiment, and FIG. 11 is an optical model diagram showing the operation of the image display device mounted on the portable terminal device of this embodiment. As shown in FIGS. 10 and 11, the mobile terminal device 9 of the present embodiment is a mobile phone in which an image display device 70 is incorporated. In the portable terminal device 9, the arrangement direction of the cylindrical lenses 3a constituting the lenticular lens 3 is the vertical direction 11, that is, the vertical direction of the image, and the longitudinal direction of the cylindrical lens 3a is the horizontal direction 12, that is, the image The horizontal direction. The arrangement direction of the first viewpoint sub-pixel 43 and the second viewpoint sub-pixel 44 in one display pixel of the display panel is the same vertical direction 11 as the arrangement direction of the cylindrical lenses 3a. In FIG. 10, only four cylindrical lenses 3a are shown for simplification of illustration, but in reality, the cylindrical lenses 3a are formed by the number of display pixels arranged in the vertical direction 11. Further, the configuration of the image display device 70 of the mobile terminal device 9 of the present embodiment other than the above is the same as that of the stereoscopic image display device 10 of the first embodiment described above.

  Next, the operation of the image display device 70 in the mobile terminal device 9 of the present embodiment will be described. As shown in FIG. 11, the backlight unit 5 emits light, and this light enters the display panel 2. At this time, the first viewpoint sub-pixel 43 of the display panel 2 displays an image for the first viewpoint, and the second viewpoint sub-pixel 44 displays an image for the second viewpoint. The light incident on the first viewpoint sub-pixel 43 and the second viewpoint sub-pixel 44 of the display panel 2 passes through these pixels and travels toward the lenticular lens 3. These lights are refracted by the cylindrical lens 3a of the lenticular lens 3 and are emitted toward the regions E1 and E2, respectively. The regions E1 and E2 are arranged along the vertical direction 11. At this time, when the observer places both eyes in the region E1, the image for the first viewpoint can be observed, and when both eyes are located in the region E2, the image for the second viewpoint is displayed. The image can be observed.

  In the mobile terminal device 9 of the present embodiment, the observer simply changes the angle of the mobile terminal device 9 to position his / her eyes in the region E1 or the region E2, and the image for the first viewpoint or the second viewpoint There is an advantage that the image can be observed. In particular, when there is a relationship between the first viewpoint image and the second viewpoint image, each image can be observed by a simple method of changing the observation angle, so that convenience is greatly improved. Note that when images for multiple viewpoints are arranged in the horizontal direction, positions for observing images with different viewpoints for the right eye and the left eye are generated, so the observer is confused and can recognize the images for each viewpoint. Disappear. On the other hand, as shown in this embodiment, when images for a plurality of viewpoints are arranged in the vertical direction, the observer can always observe the images for each viewpoint with both eyes, so that these images can be easily viewed. Can be recognized. The other effects of the mobile terminal device 9 of the present embodiment are the same as those of the stereoscopic image display device of the first embodiment described above. In addition, this embodiment can be applied to the stereoscopic image display apparatuses of the third, fourth, and fifth embodiments described above.

It is an optical model figure which shows the three-dimensional image display apparatus which concerns on the 1st Embodiment of this invention. It is a perspective view which shows the portable terminal device carrying the stereoscopic image display apparatus shown in FIG. It is an optical model figure which shows the three-dimensional image display apparatus which concerns on the 2nd Embodiment of this invention. It is a perspective view which shows a fly eye lens. It is a perspective view which shows a part of three-dimensional image display apparatus concerning the 3rd Embodiment of this invention. (A) And (b) is sectional drawing which shows typically the stereo image apparatus which concerns on the 3rd Embodiment of this invention. It is a perspective view which shows a part of three-dimensional image display apparatus concerning the 4th Embodiment of this invention. It is a perspective view which shows a part of three-dimensional image display apparatus concerning the 5th Embodiment of this invention. It is a perspective view which shows a part of three-dimensional image display apparatus concerning the 6th Embodiment of this invention. It is a perspective view which shows the portable terminal device which concerns on the 7th Embodiment of this invention. It is an optical model figure which shows operation | movement of the image display apparatus which concerns on this embodiment. It is an optical model figure which shows the stereo image display method by a parallax barrier system. It is a perspective view which shows a lenticular lens. It is an optical model figure which shows the three-dimensional display method by a lenticular lens system. It is an optical model diagram of a binocular stereoscopic image display device using a normal lenticular lens method. FIG. 16 is an optical model diagram showing a stereoscopic visible range of the binocular stereoscopic image display device shown in FIG. 15. It is a perspective view which shows a multiple image simultaneous display display. It is an optical model figure of the conventional stereoscopic image display apparatus using a lenticular lens.

Explanation of symbols

2, 106; Display panel 3, 121; Lenticular lens 3a, 122; Cylindrical lens 5, 150; Backlight unit 51, 52, 151; Optical sheet 8; Fly-eye lens 9; , 50, 60, 70; Image display device 11; Vertical direction 12, 112; Horizontal direction 41, 124; Sub-pixel for left eye 42, 123; Sub-pixel for right eye 43, 125; Pixel for first viewpoint 44, 126 Second viewpoint pixel 104; observer 105; parallax barrier 105a; slit 107; stereoscopic visible range 107a; diagonal intersection 107b; optimal observation plane 108; light source 141; right eye 142; left eye 143; Middle point 171 of the left eye 142; right eye region 172; left eye region 181, 182;

Claims (20)

At least the pixel is first juxtaposed in a direction respectively the first viewpoint pixel and the second viewpoint pixel including table示単position for displaying an image of the pixel and the second viewpoint and displays the image for the first viewpoint A plurality of display panels arranged in a matrix, and a plane perpendicular to the display panel for light emitted from the first viewpoint pixels and light emitted from the second viewpoint pixels in each display unit. A lens that is distributed in different directions that are inclined in the first direction, and an illumination member that is disposed in the vicinity of the back surface of the display panel and has a plurality of convex portions formed on the surface on the display panel side, The distance between the pixel and the convex portion is S, the focal length of the lens is f, and the arrangement pitch of the lenses is L, the first between adjacent convex portions in the illumination member. direction of distances V satisfies the following formula An image display device comprising and.
V ≦ L × S / f The image display apparatus according to claim 1 , wherein the focal length f is shorter than a distance between the lens and the pixel. The distance V is an image display apparatus according to claim 1 or 2, characterized in that the minimum value of the distance between adjacent convex portions. A plurality of display units each including at least a pixel for displaying an image for the first viewpoint and a pixel for displaying an image for the second viewpoint in the first direction, each including the first viewpoint pixel and the second viewpoint pixel. A display panel arranged in a matrix, and light emitted from the first viewpoint pixel and light emitted from the second viewpoint pixel in each display unit in a plane perpendicular to the display panel. A lens that is distributed in different directions that are inclined in the first direction, and an illumination member that is arranged in the vicinity of the back surface of the display panel and has a plurality of protrusions regularly formed on the surface on the display panel side. , Wherein the distance between the pixel and the convex portion is S, the focal length of the lens is f, and the arrangement pitch of the lenses is L, the first between the convex portions adjacent to each other in the illumination member. distance V is represented by the following formula 1 of the direction Filled, and an image display apparatus, characterized in that it is 0.6mm or less.
V ≦ L × S / f The lens is an image display apparatus according to any one of claims 1 to 4, characterized in that a plurality of cylindrical lenses whose longitudinal direction is lenticular lens arranged in parallel to each other. The image display device according to claim 5 , wherein the convex portion extends in one direction, and a direction in which the convex portion extends and a longitudinal direction of the cylindrical lens are parallel to each other. The image display device according to claim 5 , wherein the convex portions are formed in a matrix. The lens is an image display apparatus according to any one of claims 1 to 4, characterized in that a plurality of convex lens is a fly's eye lens arranged in a matrix. At least the pixel is first juxtaposed in a direction respectively the first viewpoint pixel and the second viewpoint pixel including table示単position for displaying an image of the pixel and the second viewpoint and displays the image for the first viewpoint A plurality of display panels arranged in a matrix, and a plane perpendicular to the display panel for light emitted from the first viewpoint pixels and light emitted from the second viewpoint pixels in each display unit. A lenticular lens having a cylindrical lens that is distributed in different directions inclined in the first direction, and is arranged close to the back surface of the display panel in the longitudinal direction of the cylindrical lens on the display panel side surface An illumination member formed with a plurality of convex portions extending in a direction inclined by an angle θ relative to the pixel, the distance between the pixel and the convex portion is S, the focal length of the lens is f, When the row pitch L, the pixel pitch in the longitudinal direction of the cylindrical lens and P _V, the image display device the distance V between the convex portions adjacent in the illumination member and satisfies the following expression.
V ≦ L × S × cos θ / f + P _V × sin θ At least the pixel is first juxtaposed in a direction respectively the first viewpoint pixel and the second viewpoint pixel including table示単position for displaying an image of the pixel and the second viewpoint and displays the image for the first viewpoint A plurality of display panels arranged in a matrix, and a plane perpendicular to the display panel for light emitted from the first viewpoint pixels and light emitted from the second viewpoint pixels in each display unit. the first lenticular lens having a cylindrical lens which distributes in different directions from each other inclined in a direction, a plurality of convex portions on the surface of the display panel side is arranged close to the rear surface of the display panel a matrix at the inner It includes a lighting member formed in Jo, and put a distance between the pixel and the convex portion S, a focal length of the lens f, and the array pitch of the lens L, in the longitudinal direction of the cylindrical lens When the pixel pitch is P _V, the angle to the longitudinal direction of the longitudinal direction with respect to the angle θ by the distance between adjacent convex portions of the illumination member in a direction inclined V _V, and the cylindrical lens of the cylindrical lens An image display device, wherein the distance V between adjacent convex portions of the illumination member in a direction orthogonal to a direction inclined by θ satisfies the following mathematical formula.
V _V ≦ P _V / cos θ
V ≦ L × S × cos θ / f + P _V × sin θ 11. The image display device according to claim 9 , wherein the lenticular lens is arranged so that one side of the display panel and the longitudinal direction of the cylindrical lens are parallel to each other. The image display device according to claim 9 , wherein the focal length f is shorter than a distance between the lenticular lens and the pixel. The image display apparatus according to any one of claims 1 to 12, characterized in that the light diffusing member is provided between the illumination member and the display panel. The image display apparatus according to any one of claims 1 to 13, characterized in that a three-dimensional image display device. The image display apparatus according to any one of claims 1 to 13, characterized in that the planar image display device. The image display apparatus according to any one of claims 1 to 15 wherein the display panel is characterized in that it is a liquid crystal display panel. The lighting unit is a backlight unit in which an optical sheet is disposed on the display panel side, and the optical sheet has the plurality of convex portions formed on a surface thereof. 16. The image display device according to 16 . The image display device according to any one of claims 1 to 17 , wherein the distance S is 1.4 mm or less. Mobile terminal device characterized by having an image display apparatus according to any one of claims 1 to 18. The mobile terminal device according to claim 19 , wherein the mobile terminal device is a mobile phone, a personal information terminal, a game machine, a digital camera, or a digital video.

Images